Recommended: Brain on Fire

A young New York Post reporter contracts a rare brain disorder, recovers against the odds, then puts her restored mind to use investigating the disease's medical underpinnings. Cahalan's account is swift and haunting and holds relevance beyond her dramatic case. Researchers are recognizing that autoimmune diseases of the nervous system—hers is called anti-NMDA receptor encephalitis—are more common than previously thought. As barriers collapse between immunology, neurology and psychiatry, investigators are gaining a clearer understanding of the roots—and true nature—of mental illness.